1. Technical Field
The present invention relates to a projection lens including a lens group holding tube that moves in the optical axis direction, and to a projector that projects an image displayed on an image display device via a projection lens.
2. Related Art
JP-A-2012-220915 describes a projection lens incorporated in a projector. The projection lens described in JP-A-2012-220915 includes a lens barrel and an attachment tubular member for fixing the lens barrel to a fixing portion of the projector. The lens barrel includes a plurality of lenses and a barrel that holds the lenses in such a way that the outer circumferences thereof are held. The attachment tubular member includes an annular plate portion, a tubular portion that extends forward in the projection direction (toward enlargement side) from the outer-circumferential-side end portion of the plate portion, and a flange that protrudes outward from the tubular portion. The plate portion is fixed to an end surface of the lens barrel that is the end surface on the rear (reduction side) in the projection direction. In the state in which the plate portion is fixed so that the attachment tubular member is attached to the lens barrel, the tubular portion is located on the side facing the outer circumference of the lens barrel.
In the projection lens described in JP-A-2012-220915, the attachment tubular member including the flange supports the lens barrel in the form of a cantilever. Therefore, when the projection lens is fixed to the fixing portion of the projector via the flange, and impact externally acts on the projection lens, a large load acts on the attachment tubular member and the attachment tubular member could therefore be broken. Further, in the projection lens described in JP-A-2012-220915, the attachment tubular member including the flange includes the tubular portion located on the side facing the outer circumference of the lens barrel, resulting in a problem of an increase in the radial size of the projection lens.